Tools for the abrasive treatment of the interior of hollow bodies



1961 J. v. RONALDSON ET AL 2,966,766

TOOLS FOR THE ABRASIVE TREATMENT OF THE INTERIOR OF HOLLOW BODIES Filed July 25, 1958 2 Sheets-Sheet 1 2 9 3b 51 I 1 21 [VI Emma James Victor Ronaldson 8c Ra lph Cooper Hollingworth 1961 J. v. RONALDSON ET AL 2,966,766

TOOLS FOR THE ABRASIVE TREATMENT OF THE INTERIOR OF HOLLOW BODIES Filed July 25, 1958 2 Sheets-Sheet 2 'ictor Rona ldson E ni goopgyfio llingworth ATTORNEX! Patented Jan. 3, 1961 1 paste, metal with a diamond impregnated surface or a diamond set surface, or a metal body coated with other 2,966,766 hard materials, such as tungsten, carbide, stellite and so TOOLS FOR THE ABRASIVE TREATMENT OF THE INTERIOR F HOLLOW BODIES James V. Ronaldson, 35 Downsway, Sanderstead, England, and Ralph Cooper Hollingworth, 59 Ring Road, Stoneygate, England Filed July 25, 1958, Ser. No. 751,059

4 Claims. (Cl. 51-184.1)

The present invention relates to tools intended for use in the abrasive treatment of the internal surfaces of tubular bodies for the purpose of grinding, cleaning, descaling, fettling, smoothing, cutting, scoring and other operations which can conveniently be performed by an abrasive tool.

The invention has primarily been devised to deal with the abrasive treatment of the interior walls or bores of tubes and will, for convenience only, be hereinafter described in this particular connection, it being understood that the tool can be used in other applications involving similar principles, for instance in other forms of hollow body, sockets, or rings. Such further and analogous applications are, moreover, to be interpreted as included in the term the abrasive treatment of the internal surfaces of tubular bodies which is used hereafter in this specification and the claims.

In brief, the tool of this invention comprises a mounting head intended to be introduced into and rotated in the tubular body to be treated, and a plurality of abrasive elements carried by said head, so as to be movable outwardly of said head under and into contact with the work under centrifugal action, in response to the aforesaid rotation of the head.

Thus, in practice, the rotation of the head causes the abrasive elements to be swung outwards to contact and wipe over the surface under treatment, being applied by centrifugal force against the work under a uniform but yielding pressure to perform the necessary grinding, scaling, cutting or other action which is catered for.

These abrasive elements may take various forms, but preferably they will have a rounded contact surface to engage the work. In a preferred arrangement, they comprise cylindrical discs or rolls and these are mounted for outward swinging in the head, which for example may comprise a pair of opposed plates, by eccentric pivotpins arranged in a ring around the head.

The elementsmay, moreover, be of variable number in the head and of various sizes, that chosen being largely determined by the size of the head and thus of the tubular body with which the tool is to be used. As an example,

with a circular head of a diameter of about '3" and a thickness of about 1%, formed by parallel spaced plates, each of about /4 thickness, we may conveniently use three abrasive elementsof adiameter ofabout 1 /2", and -a thickness of aboutl", each-pivoted at a radial distance of about 7 from its edge and about the same distance inwards from the periphery of the plates.

The elements may, moreover, be of any suitable abrasive constituent, for example comprising grits of silicon carbide or aluminum oxide, which are vitreous, silicon, resin or lacquer bonded. The grit size may, again, vary to suit particular types of work, so that, in fact, the

stones may either have a great coarse grit or one as fine as, say, 60 grit.

These abrasive elements may, of course, be of materials other than those specified above, for example natural or synthetic stones, box wood for use with diamond on, so as to render the tool suitable as a'reamer for bore holes. Again the elements may, in fact, be ,used for polishing purposes and comprise metal, plastic or wood faced with felt or pressed cotton or felt in layered form.

As has already been indicated, the abrasive elements will conveniently be of disc or roller form, and where used for cutting purposes we will preferably employdiscs which are of thin Section.

As a further feature of the invention, the head may be provided with stop means to limit the centrifugal throw of the elements in response to the rotation of the head. Again, to cater for adjustment of difierent sizes of work, the pivot pins or other means about which'the elements are movable may be adjustable in relation to the body of the head.

For the purpose of projecting the head into the work and rotating it therein, the tool will most conveniently be provided with a stem, for example a bar or rod, which can be rotated, or has a part thereof rotated, by appropriate means, for example a motor which remains outside the tube.

Where the tool includes a stem as outlined above, the latter may have, along the length thereof, a plurality of heads carrying abrasive elements, this enabling different zones of a tube to be dealt with simultaneously.

The abrasive treatment by the various heads 'on a single .stem are not necessarily the same and, for example, the successive heads maybe arranged to produce, say, grinding of vsuccessivedegrees of fineness along the length of the tool. .By this means, one pass of thetool through the work can be used to produce a coarse grinding, .followed by a finefgrindin g, 'followedfby .finishing and smoothing.

Furthermore, it will be understood that the .tool can carry, on a stem and along' with one or more abrading heads or equivalent, other treatingdevices having a lessabrasive action, for example a polishing mop.

It will further be understood that spaced abrasive ,or other heads as described above may be sufficient to ceritre the tool'in the tube under treatment. A special mounting may, however, be provided "for this purpose, whether or not the tool is multi-headed.

According to a further feature of the invention, and in an instance where the head is carriedvby a stem, this latter has a channel therein for the fiow of liquid to the head, and in ,which'the tool is laterally apertured at the head for the app'iation of liquid against the work.

Various forms of the invention are illustrated, by way of example, in th eaccompanying drawings, toiivhichreferences will now be made. In these drawings:

Figure 1 is an endview of a simple form of grinding tool in accordance withthis invention.

Figure 2 is a side view of the-headshown in Figure -1.

"Figure 3 is a side view, partly in vertical section, diagrammatically illustrating the use of a tool witlila head i or anc wit Fig r 's'landl Figure '4 a cross'sec'tion on'IV-IV of Figure 3 diagrammatically illustrating the performance of the tool in a tubular body of non-uniform diameter.

Figure 5 is a side view, similar to that of Figure 3, but illustrating a modified form of tool.

Figure 6 is a similar, and a diagrammatic, illustration of another method of use of the tool according to the invention, and

Figure 7 is yet another side view showing part of a tool equipped with different forms of abrasive elements.

The tool head illustrated in Figures 1 and 2 is formed by a pair of spaced parallel mounting plates 1 and 2 which are connected by a bolt 3, the latter being screw "2,966,766 I 7 I A I,

threaded, at least at its ends, to receive the fastening .nuts 4 and 5 at the two sides of the plates 1 and 2.

The threaded rear end 6 of, the bolt 3 is adapted to be secured to an operating stem by which the head is manipulated and rotated in performing its abrading work.

Mounted between the plates, with their axes parallel to that of the bolt 3, are three abrading elements 7 in the form of cylindrical abrading rollers, these each being pivoted eccentrically about a pin 8. The pins 8 are arranged in a ring around the spaced plates 2 and each is positioned so that the edge of the associated element 7 will project outwardly from the periphery of the plates 1, 2. Further fixed pins 9 and 10 are associated with each element 7 and form stops determining the outer and inner limits of throw of the element 7 concerned.

Hence, when inserted into a tube, such as diagrammatically indicated at 11 in Figures 1 and 2, and rotated,

'the tool will throw the elements 7 outwardly under centrifugal action so that they bear yieldingly on, and

sweep over, the inner wall of the tube to perform the abrading, cutting or other action to which they are appropriate.

Thus, the tool may be provided wtih a stem 12, as indicated in Figure 3, and this be rotated, egg. from a motor 13 through a flexible drive shaft 14. To centre the head 1, 2 in the tube 11 under treatment, it may be provided with a mounting fitting such as the element 15 depicted, this being in the form of a spider and recessed at 16 to fit against and in the end of the tube, and having a central hub for rotatably supporting the stem 12.

The tool is, of course, not limited to use with a particular size of tube, and Figures 3 and 4 indicate the way in which the same tool will operate in tubes of different sizes, a larger size than 11 being indicated at 11 in these drawings. Similarly, the tool can be used to .operate on an internally-tapered tube.

Figure 5 serves to illustrate other features of the invention, viz. that the tool and its driving means may be of a portable type, for example having an operating casing 17 with a butt 18 which can be gripped by the operator. The casing 17 serves to house a motor 19 which, through gearing 20, drives a stem 21 carrying the abrasive head 1, 2, the control of the rotation of the tool being here exercised by a trigger 22.

Another feature which is illustrated by Figure 5 is the arrangement whereby the tool is designed for the supply of coolant or lubricant liquid to the actual working zone, and in this particular instance the liquid concerned is introduced through a line 23 into a pipe 24 passing through the casing 17 and into a hollow tube 25 mounted within the stem 21. In this case, the bolt 26 which serves to attach the plates 1 and 2 together 4 may be provided with a plurality of such heads arranged in succession and, for example, arranged to contact each zone of the tool in succession, for example for the purpose of successively treating each zone with abrading elements of different fineness. Thus, the tool illustrated in Figure 6 is provided with three heads, 29, 30 and 31 of different abrasive quality; the last of them may even carry polishing elements.

Finally, Figure 7 illustrates a form of the tool in which the cylindrical abrading rollers 7 illustrated in the preceding figures are replaced by discs 32 which are thin and are therefore adapted to perform a cutting function.

The invention is, of course, not limited to the specific examples which have been described above and many modifications and changes can be made in the form or disposition of the parts to arrive at the prescribed object.

Thus, for example, the abrasive elements may be carried by arms which are adapted to swing outwards, as a result of rotation of the tool, so as to be applied against the work. In this case the elements may conveniently be cylindrical and pivoted to the parent arm or to a pair of parallel arms between which it is disposed. The arms themselves may be pivoted directly to a stem or to a structure secured on such a stem.

In this last mentioned arrangement adjustable means may be provided to limit the swing of the arms, for instance a cylindrical stop which can be set at required positions along the stem or head to abut the arms when these are swung outwards by the centrifugal action. This enables the tool to be set to a requiredfinal diameter for the bore.

What claim:

1. A tool adapted for abrasive treatment of a tubular body having a first inside diameter, comprising a rotatable rod, at least one first disc having a diameter smaller than said first diameter and secured at its center to said rod, a plurality of first pins secured normal to said first disc adjacent the perimeter thereof, an abrasive roller eccentrically journalled about each said first pin, said first pins being secured in a concentric ring on said disc, and a plurality of second pins secured normal to said first disc between said ring and said perimeter, each said first pin lying between a said second pin and the center of the roller journalled thereabout.

2. A tool according to claim 1 further comprising a plurality of third pins secured normal to said first disc and arranged to limit the inward movement of said rollers. p

3. A tool according to claim 1 wherein said first pins are also secured normal to a second disc secured at its center on said rod and extending parallel to said first disc.

4. A tool according to claim 1 wherein said rod is hollow and has orifices therein through which coolant is ejected with said rotation.

References Cited in the file of this patent UNITED STATES PATENTS 267,132 Belding Nov. 7, 1882 958,205 Ainge May 17, 1910 1,803,701 Grover May 5, 1931 2,229,314 Solbrig Jan. 21, 1941 2,442,624 Talboys June 1, 1948 

